[saeedi]

Hi there,

I am new to OpenFoam and just started working with that.

I have conducted a test on a 2D cylinder at Re=100 (laminar), just to make sure that the basics of my openfoam simulation are OK.

The simulation went well and I also made an animation for the flow evolution which can be downloaded from here:

https://www.dropbox.com/s/zqnvxg7hbt...-SLOW.avi?dl=0

and here is with the vectors superimposed:

https://www.dropbox.com/s/e3mvvvxnm0...ector.avi?dl=0


There is some thing that puzzles me a bit. Although it is quite obvious from the contour structures and topology that the flow is from left to right, in the animation it seems that those high U contours are begin convected from the outflow boundary to the cylinder. It is not a visual mistake as I refined the time step and got the same result.

I suspect there might be some more subtleties related to OpenFoam. I checked whatever I knew but could not find the problem. If I ran the animation in the reverse order then it looks quite nice!

if you look at the flow development, from time=0 to the first couple of snapshots, it shows that the flow is developing correctly and I think that is an indication that the zone order is right. But suddenly we see that reverse behavior around time=1.


I'd appreciate your help.